It's been many years since I dealt with this, but I think you want your communication template on WFASSIGNMENT rather than SR. Then you have the CURRENTMEMO & LASTMEMO options as attributes on the WFASSIGNMENT record. Then you can link back to the SR attributes.
When you start from SR, you're only going to be able to get what exists in the database for the assignment. That's OK if you send the communication outside of the workflow, but inside the workflow, the communication is sent prior to the record being saved in the database. This leads to you getting the wrong memo. I'm assuming your relationship you left off the DESC in the order by, otherwise that would be a problem too.
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Steven Shull
Naviam
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